This invention relates to apparatus for switching the motion of a transfer roller of an inking device and a water feed device of a printing machine in an interlocked manner with a manual operation and the operation of an impression cylinder.
A conventional rotary press comprises a number of printing units corresponding to the number of colors to be printed. FIG. 1 of the accompanying drawing shows a printing unit of a multicolor sheet fed rotary press, which comprises a plate cylinder 2, a rubber cylinder 3 which rotates in contact therewith, and an impression cylinder 4 which rotates in contact with the rubber cylinder 3. A transfer cylinder 5 is provided between adjacent printing units. Above and in front of the plate cylinder 2 are disposed an inking arrangement 6 including a plurality of roller groups and a water feed device 7 for supplying ink and water to a platen mounted on the plate cylinder 2, these forming an image which is transferred onto the surface of the rubber cylinder 3. A printing paper supplied to an paper inserting device or a printing unit of a preceding stage is clamped by jaws of the transfer cylinder 5 and wrapped about the same. The paper is then passed between the rubber cylinder 3 and the impression cylinder 4 while being clamped by the jaws thereof, during which the image on the rubber cylinder 3 is transfer-printed onto the paper. The paper thus printed is transferred to a succeeding printing unit by a transfer cylinder 5 on the downstream side or to a delivery apparatus.
The inking arrangement 6 comprises an ink fountain containing printing ink, an ink fountain roller 9, a swinging roller 10, a transfer roller 12 disposed between the ink fountain roller 9 and the swinging roller 10 and supported by a swinging arm 11. The transfer roller 12 is reciprocated between the ink fountain roller 9 and the swinging roller 10 by the arm 11 swung by the rotation of a cam not shown so as to alternately engage the peripheral surfaces of both rollers 9 and 10 thus transferring the ink on the ink fountain roller 9 to the swinging roller 10. The ink transferred to the swinging roller 10 is supplied to the platen on the plate cylinder 2 via the plurality of roller groups. Various elements of the water feed device 7 are constructed substantially identical to the elements of the inking device 6 so that corresponding elements are designated by primed reference numerals. During printing the transfer roller 12 and 12' of the inking device 6 and the water feed device 7 reciprocated between roller 9 and 10 (9' and 10'). When these transfer rollers 12, 12' are operated in the absence of printing paper between rubber cylinder 3 and the impression roller 4, ink and water would be supplied to the impression cylinder 4 thus contaminating the same causing trouble. For this reason the printing press is constructed such that, at the commencement or the interruption of the printing operation the transfer roller 12 is stopped in contact with the swinging roller 10 so as not to supply ink and water. Where it is desired to stop supply of the ink of a single color and water, the motion of the transfer roller 12 of a printing unit 1 of that color is stopped.
The rubber cylinder 3 is constructed such that it is journalled by eccentric bearings and at the time of off-printing by rotating the bearings the peripheral surface of the rubber cylinder 3 is separated from the plate cylinder 2 and the impression cylinder 4 so as to switch from the so-called cylinder-in state to the cylinder-out state. As above described during the off-printing state, as it is necessary to stop supply of water and ink and to bring the rubber cylinder 3 to the cylinder-out state it is desirable to interlock the switching operation between operation and stop of the transfer roller with the in and out operations of the rubber cylinder 3 in order to simplify the operation. However, if the interlocking were made constantly, where it is desired to stop supply of ink and water for only one color, a cylinder-out state would be resulted thus disabling paper feed. Accordingly, it is necessary to make independent from each other the switching operation of the transfer roller 12 and the switching operation of the cylinder in and out operation of the rubber cylinder 3.